Wireless communication systems provide User Equipment (UE), such as smartphones, tablet computers, and other media devices, wireless access to communication services and allow users to move about and communicate over the air with access communication networks. Data communication networks, such as Long Term Evolution (LTE), exchange data packets with UEs to provide services, such as internet access, media streaming, voice calls, and text messaging.
Using LTE, a UE detects and attaches to an LTE base station, such as an evolved NodeB (eNodeB). eNodeBs support the exchange of signaling and data to LTE network elements, such as Serving Gateways (S-GWs), Mobility Management Entities (MMEs), Packet Data Network Gateways (P-GWs), Policy Charging Rules Functions (PCRFs), and other network elements.
Internet Protocol Multimedia Subsystem (IMS) is a popular control system to facilitate the exchange of Internet Protocol (IP) packets between UEs for media sessions and other data transfer services. The UE registers an IP address with the IMS systems over the IP access networks and use the registered IP address to exchange messaging for the IP communication sessions. A UE may register with an IMS system directly using various access systems, including LTE, Code Division Multiple Access (CDMA), Global System for Mobile Communications (GSM), Ethernet, and other access systems.
Wireless Priority Services (WPS) is a federally administered service which provides emergency preparedness and national security personnel access to cellular networks for high-priority calls during periods of network congestion, such as during an emergency situation. WPS approved personnel register UEs with a participating network provider and may utilize WPS to initiate a high priority call by entering a WPS prefix to a destination address, such as *272 followed by a ten-digit mobile number.
While a media session invite for an approved UE may be transferred to the IMS system over an untrusted network, such as a Wireless Fidelity (WiFi) network to a carrier secure gateway, the LTE network may be preferred to allow full priority services to be initiated over a trusted network. An IMS may use an alternative network to receive a media session invite having a WPS prefix from a UE, but unfortunately, current interactions between a WPS approved UE and IMS systems are not effective for redirecting the media session invite having a WPS prefix from an untrusted network to an LTE network.